The Oconee Coal Member of the Mattoon Formation of the McLeansboro Group is here named in Shelby, Cumberland, Effingham, and Jasper Counties, IL. It lies 25 to 40 ft above the Loudon Coal Member and 60 to 110 ft below the Shelbyville Coal Member of the Mattoon Formation. Thickness is 1 ft at type section. Age is Late Pennsylvanian (Missourian).
Source: GNU records (USGS DDS-6; Reston GNULEX).
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
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